FIELD OF THE INVENTION

The present disclosure relates to a pressure-sensitive adhesive article for preventing peeling off of concrete structure and construction method thereof.

BACKGROUND

Conventionally, a method of applying a coating agent or the like for preventing peeling of concrete onto a surface of a concrete structure was used in order to prevent peeling off of a concrete piece from concrete structures such as a bridge, tunnel, elevated road, or the like.

Patent document 1 (Japanese Patent Publication No. 4347757) describes applying onto the concrete structure "a mesh fabric for preventing peeling off of concrete, made by applying or impregnation coating an ethylene-vinyl acetate copolymer emulsion or an acrylic resin emulsion onto a mesh fabric with a mesh size of 2 to 20 mm, in which the number of axis formed by synthetic fibers, glass fibers, or carbon fibers wherein the total amount of yarn per axis is 300 to 10000 decitex, is two to four".

Patent document 2 (Japanese Unexamined Patent Application Publication No. 2004-027718) describes applying onto a concrete structure "a sheet for repairing, reinforcing, or preventing deterioration of the concrete structure, forming an adhesive layer containing a pressure-sensitive adhesive or hot melt adhesive on an adhesive surface onto the concrete structure of an adhesive coating layer in conjunction with adhering a protective layer and the adhesive coating layer containing a reinforcing layer and/or pasting layer".

SUMMARY

In the conventional method, after a reinforcing fiber layer is applied after coating an adhesive on a surface of a concrete structure, or after an article coated with an adhesive on one surface of a reinforcing fiber layer was applied to a surface of a concrete structure, a surface treating agent must be further applied to another surface of the reinforcing fiber layer, and thus a simpler construction method was in demand.

Furthermore, peeling off of a concrete piece from a concrete structure such as a bridge, tunnel, elevated road, or the like may lead to accidents or the like, and therefore, further improvement of peeling prevention performance of the concrete piece was also in demand.

In view of the foregoing, an object of the present invention is to provide: a pressure-sensitive adhesive article for preventing peeling off of a concrete structure that can be constructed in a short period of time as compared to a conventional construction method, and can further improve peeling prevention performance of a concrete piece; and construction method thereof. According to an embodiment of the present disclosure, a construction method of a pressure- sensitive adhesive article that prevents peeling off of a concrete structure is provided, including: a step of directly applying onto the concrete structure the pressure-sensitive adhesive article that contains a pressure-sensitive adhesive layer containing a pressure-sensitive acrylic polymer and inorganic fine particles, and a fibrous sheet provided in the pressure-sensitive adhesive layer, where the pressure- sensitive adhesive layer is present on both main surfaces of the article.

According to another embodiment of the present disclosure, a construction method of a pressure- sensitive adhesive article that prevents peeling off of a concrete structure is provided, including: a step of applying a surface treating agent to form a surface treated layer; and a step of directly applying onto the concrete structure the pressure-sensitive adhesive article that contains a pressure-sensitive adhesive layer containing a pressure-sensitive acrylic polymer and inorganic fine particles, and a fibrous sheet provided in the pressure-sensitive adhesive layer, where the pressure-sensitive adhesive layer is present on both main surfaces of the article.

According to yet another embodiment of the present disclosure, a pressure-sensitive adhesive article used in the construction method is provided, containing: a pressure-sensitive adhesive layer containing a pressure-sensitive adhesive acrylic polymer and inorganic fine particles; and a fibrous sheet provided in the pressure-sensitive adhesive layer; wherein the pressure-sensitive adhesive layer is present on both main surfaces of the article.

With the construction method of a pressure-sensitive adhesive article that prevents peeling off of a concrete structure of the present disclosure, the pressure-sensitive adhesive article has a fibrous sheet that is provided inside a pressure-sensitive adhesive layer, where the pressure-sensitive adhesive layer is present on both main surfaces of the article, and thus the integral pressure-sensitive adhesive article integrated can be directly applied once to a concrete structure, and therefore, an operation can be completed in a shorter amount of time than a conventional construction method that requires applying means during construction.

The pressure-sensitive adhesive article of the present disclosure uses a pressure-sensitive adhesive containing a pressure-sensitive adhesive acrylic polymer and inorganic fine particles, and therefore, the peeling prevention performance of a concrete piece can be improved as compared to a conventional product.

The description above should not be considered as a complete disclosure of all embodiments of the present invention or of the advantages related to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the pressure-sensitive adhesive article of an embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of a concrete structure applying the pressure-sensitive adhesive article of FIG. 1; FIG. 3 is a cross-sectional view of the pressure-sensitive adhesive article of another embodiment of the present disclosure;

FIG. 4 is a side surface view of a push-off testing device; and

FIG. 5 is a front surface view of a push-off testing device.

DETAILED DESCRIPTION

A detailed description for the purpose of illustrating representative embodiments of the present invention is given below, but these embodiments should not be construed as limiting the present invention.

The pressure-sensitive adhesive article according to an embodiment of the present disclosure is a pressure -sensitive adhesive article that contains: a pressure-sensitive adhesive layer containing a pressure- sensitive adhesive acrylic polymer and inorganic fine particles; and a fibrous sheet provided in the pressure -sensitive adhesive layer, where the pressure-sensitive adhesive layer is present on both main surfaces of the article.

FIG. 1 illustrates a perspective view of a pressure-sensitive adhesive article of an embodiment of the present disclosure, and FIG. 2 illustrates a cross-sectional view of a concrete structure applying the pressure- sensitive adhesive article. As illustrated in FIG. 1 and 2, a pressure-sensitive adhesive article 1 provides a pressure-sensitive adhesive layer 2 and a fibrous sheet 3 provided in the pressure-sensitive adhesive layer 2.

The pressure-sensitive adhesive layer 2 contains a pressure-sensitive adhesive acrylic polymer from the perspective of excellent peeling prevention performance of a concrete piece. Herein, "pressure- sensitive adhesive" means that the storage elastic modulus (G) measured at 10 radians / second at an application temperature (can be measured at 20°C to 22°C) is less than 3 ^χ 10 ⁵ pascals (Dahlquist standard). "Polymer" follows the definition of "polymer" by the Polymer Nomenclature Commission of the International Union of Pure and Applied Chemistry (IUPAC)

(http://main.spsj .or jp/c 19/iupac/Recommendations/glossary36.html) .

The pressure-sensitive adhesive acrylic polymer is preferably a polymer obtained by polymerizing a first monomer containing at least one type of (meth)acrylic acid ester of a non-tertiary alcohol with 4 to 20 carbon atoms in an alkyl group, and a second monomer copolymerizable with the first monomer. However, the second monomer is a monomer that is different from the first monomer. Herein, "(metha)acrylic" refers to acrylic or methacrylic (may be referred to as methacrylic), and similar compounds are also the same.

The first monomer is preferably a monomer providing a polymer with a glass transition temperature of 0°C or lower if homopolymerized. Herein, the glass transition temperature refers to a temperature at a peak position of tan5 (same hereinafter) in dynamic viscoelasticity measurement (frequency can be 1.0 Hz and heating rate can be 5°C/min). The first monomer is preferably a monofunctional (meth)acrylic acid ester of a non-tertiary alkyl alcohol with 4 to 20 or 4 to 18 carbon atoms in an alkyl group. Examples of the first monomer include n-butyl acrylate, n-hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethyl hexyl acrylate, isononyl acrylate, n-decyl acrylate, n-dodecyl acrylate, octadecyl acrylate, and mixtures thereof.

The second monomer has at least one ethylenically unsaturated group, and is preferably a monomer providing a polymer with a glass transition temperature that exceeds 0°C if homopolymerized. Examples of the second monomer include (meth)acrylic acid, N-vinyl pyrrolidone, N-vinyl caprolactam, N,N-dimethyl acrylamide, and other substituted (meth)acrylamides, acrylonitrile, isobomyl acrylate, acrylates of alcohols with 1 to 3 carbon atoms in an alkyl group, carboxyethyl acrylates, and mixtures thereof. From the perspective of peeling preventing properties, the second monomer is preferably (meth)acrylic acid, N,N-dimethyl acrylamide, and isobornyl acrylate. If a basic monomer such as the substituted (meth)acrylamide or the like is used as the second monomer, a weakly basic tertiary amine compound or the like can be used.

With regard to the mass ratio of the first monomer and second monomer (first monomer/second monomer), the first monomer is preferably 50 mass part or more, 60 mass parts or more, or 70 mass parts or more, and 100 mass parts or less, and the second monomer is preferably 0 mass parts or more, 2 mass parts or more, or 5 mass parts or more, and 50 mass parts or less, 40 mass parts or less, or 30 mass parts or less, from the perspective of balance between initial adhesive force under low

temperatures and static shear strength under high temperatures.

The content of the pressure-sensitive adhesive acrylic polymer is preferably 50 mass% or more, 70 mass% or more, or 90 mass% or more and 99 mass% or less, 97 mass% or less, or 95 mass% or less based on the total amount of the pressure-sensitive adhesive layer 2.

The pressure-sensitive adhesive layer 2 further contains inorganic fine particles from the perspective of being able to suitably reinforcing a concrete structure, in other words, being able to improve the peeling preventing properties, water resistance, and the like of a concrete piece. The inorganic fine particles is preferably silica fine particles or fine particles of a mineral for example. The inorganic fine particles may either be solid fine particles or hollow fine particles. The shape of the inorganic fine particles is not restricted to spherical fine particles, and fine particles with different shapes such as a flat shape or the like can be used.

The inorganic fine particles preferably contain first inorganic fine particles having a particle diameter (median diameter, same hereinafter) of 1 um or more, 5 μπι or more, or 10 um or more, and 500 μπι or less, 300 um or less, or 100 μπι or less, from the perspective of a reinforcing effect of the pressure- sensitive adhesive article.

The content of the first inorganic fine particles is preferably 0.1 mass parts or more, 1 mass parts of more, or 3 mass parts or more, and 20 mass parts or less, 18 mass parts or less, or 15 mass parts or less with regard to 100 mass parts of the pressure-sensitive adhesive acrylic polymer, from the perspective of a reinforcing effect of the pressure-sensitive adhesive article.

The inorganic fine particles preferably further contains second inorganic fine particles having a particle diameter of 0.0001 um or more, 0.001 μτη or more, or 0.005 μτη or more and 1 μπι or less, 0.1 μπι or less, or 0.05 μτη or less, from the perspective of being able to suitably reinforce a concrete structure and ensuring dispersibility of the first inorganic fine particles into the pressure-sensitive adhesive layer 2. In this case, with regard to the mass ratio of the first inorganic fine particles and second inorganic fine particles (first inorganic fine particles/second inorganic fine particles), the amount of first inorganic fine particles is preferably 1 mass part or more, 3 mass parts or more, or 5 mass parts or more and 100 mass parts or less, 20 mass parts or less, or 10 mass parts or less, and the amount of second inorganic fine particles is preferably 0 mass parts or more, 0.5 mass parts or more, or 1 mass part or more and 50 mass parts or less, 10 mass parts or less, or 5 mass parts or less for example.

The first inorganic fine particles can be K15 manufactured by 3M Company and Microsphere M-600 manufactured by Matsuyama Co., Ltd. for example. The second inorganic fine particles can be A-200 and R-972 manufactured by Nippon Aerosil Co., Ltd. for example.

The pressure-sensitive adhesive layer 2 may further contain a tackifier. Examples of the tackifier include hydrocarbon resins, terepene phenol resins, rosin resins, rosin ester resins, hydrides thereof, and the like. Examples of available tackifiers include RegalrezTM1085, RegalrezTM1094, RegalrezTM6108, GegalrezTM3102 manufactured by Eastman Chemical Company Japan, Arkon P- 140 manufactured by Arakawa Chemical Industries, Ltd., and the like.

The content of the tackifier is preferably 10 mass parts or less or 5 mass parts or less with regard to 100 mass parts of the pressure-sensitive adhesive acrylic polymer. The content of the tackifier is preferably 0.5 mass parts or more with regard to 100 mass parts of the pressure-sensitive adhesive acrylic polymer for example.

The pressure-sensitive adhesive layer 2 may further contain a conventionally known additive used in pressure-sensitive adhesives such as polymerization initiators, crosslinking agents, plasticizers, fillers, anti-aging agents, ultraviolet absorbers, pigments, and the like, in addition to the aforementioned components.

The thickness of the pressure-sensitive adhesive layer 2 (thickness including the fibrous sheet 3) is preferably 50 μπι or more, 70 μπι or more, 100 μπι or more, or 200 μπι or more and 3000 μπι or less, 1000 μτη or less, 600 μπι or less, or 400 μπι or less for example.

The fibrous sheet 3 is formed by a plurality of mutually intersecting fibers 3 a. Specifically, in the fibrous sheet 3, a plurality of fibers 3 a are mutually intersecting in a condition oriented randomly or in two or more directions, and at the intersecting point, the fibers 3 a are bonded by one or more entanglement, fusion, or adhesion. The fibrous sheet 3 is preferably woven material, knitted material, or nonwoven material for example. Woven material/knitted material as referred to herein is a multiaxial woven material/knitted material such as biaxial woven material/knitted material, triaxial woven/knitted material, or the like where a plurality of fibers are oriented in two directions or more. In the pressure-sensitive adhesive article 1 illustrated in FIG. 1 and 2, the fibrous sheet 3 is a biaxial woven material where the plurality of fibers 3a are woven together in a condition oriented in two directions (substantially orthogonal direction).

The fibers 3a may either be a monofilament or multifilament. The fibers 3a are preferably formed from at least one from glass, vinylon, and aramid, and is preferably formed from glass from the perspective of tensile elasticity, and preferably formed from vinylon and/or aramid from the perspective of compatibility with a pressure-sensitive adhesive. The thickness of the fibers 3a is preferably 10 tex or more, 20 tex or more, or 40 tex or more and 100 tex or less, 90 tex or less, or 80 tex or less.

The fibrous sheet 3 is preferably biaxial woven material or triaxial woven material, and more preferably a biaxial woven material or triaxial woven material where the fibers 3a are sealed by fusing or adhering, from the perspective of being able to suitably reinforce a concrete structure. The weaving the biaxial woven material or triaxial woven material is preferably a plain weave, twill, satin, leno weave, or mock leno weave.

The thickness of the fibrous sheet 3 is preferably 10 um or more, 20 um or more, 30 um or more, 50 um or more, or 100 um or more and 2000 um or less, 1000 um or less, 500 um or less, 400 um or less, or 300 um or less for example. Furthermore, the density of the fibers 3a in the fibrous sheet 3 is preferably 1 fiber / 25 mm or more, 2 fibers / 25 mm or more, or 3 fibers / 25 mm or more and 10 fibers / 25 mm or less, 7 fibers / 25 mm or less, or 5 fibers / 25 mm or less from the perspective of enabling following of deformation while suitably reinforcing a concrete structure. The tensile strength of the fibrous sheet is preferably 500 N / 25 mm or more, 750 N / 25 mm or more, or 1000 N / 25 mm or more and 2500 N / 25 mm or less.

L160MA100LF manufactured by Unitika Ltd. is available as an example of the fibrous sheet 3.

The fibrous sheet 3 is provided in the pressure-sensitive adhesive layer 2. In other words, the pressure -sensitive adhesive layer 2 is present on both main surfaces of the fibrous sheet 3, and both main surfaces of the fibrous sheet 3 are not exposed. Furthermore, as illustrated in FIG. 2, a gap occurring between the plurality of fibers 3a forming the fibrous sheet 3 is filled by a pressure-sensitive adhesive configuring the pressure-sensitive adhesive layer 2. Movement of the fibers is suppressed due to the pressure-sensitive adhesive filling the gap between the fibers, and therefore, the peeling prevention performance of a concrete piece can be further improved.

At least one of the thicknesses (shortest distance) from the main surface of the fibrous sheet 3 and both main surfaces of the pressure-sensitive adhesive layer 2 is preferably 100 μπι or less, 80 μπι or less, or 50 μπι or less and 1 μπι or more, 5 μπι or more, or 50 μπι or more. In this case, the main surface of the pressure-sensitive adhesive layer 2 where the shortest distance from the main surface of the fibrous sheet 3 is at the aforementioned predetermined value or less is pasted to a concrete structure, and therefore, the concrete structure can be suitably reinforced.

FIG. 3 is a cross-sectional view illustrating another embodiment of the pressure-sensitive adhesive article. As illustrated in FIG. 3, a pressure -sensitive adhesive article 11 may further provide substrate 5 on one surface side of the pressure-sensitive adhesive layer 2.

The substrate 5 is preferably a film, sheet containing foam material, nonwoven material, honeycomb structure, combinations thereof, or the like, and the substrate 5 is preferably a material functioning as a protective layer, sound absorbing material, or the like that can provide performance such as weather resistance, stain resistance, water resistance, saline resistance, and the like. The film is preferably a polyethylene film, polypropylene film, polyester film, polycarbonate film, polyvinyl chloride film, polyvinylidene chloride film, polystyrene film, polyamide film, and the like for example. The sheet containing foam material is preferably acrylic foam material sheet, polyethylene foam material sheet, chloroprene foam material sheet, urethane foam material sheet, and the like for example. The sheet containing a foam material may be a sheet having pressure-sensitive adhesive properties itself. The acrylic foam tape (RT8016 manufactured by 3M Japan Limited) and the like can be purchased as the sheet. The nonwoven material is preferably nonwoven material formed from polyethylene terephthalate (PET) and other polyesters, high density polyethylene or polypropylene and other polyolefins, nylon and other polyamides, polyvinyl alcohols, polyacrylonitriles, cotton, linen, and other cellulosic pulp natural fibers, or rayon. The honeycomb structure has a plurality of cells (gaps) divided by a partition wall, and the cells are opened on both ends in a height direction (in other words, thickness direction of the honeycomb structure). The honeycomb structure is not restricted to structures where the planar shape of the cells is hexagonal, and may be triangular, square, pentagonal, octagonal, and other polygonal shape, a waveform shape, circular, and the like. The honeycomb structure may be configured by a material containing an inorganic compound or metal from the perspective of incombustibility. Examples of the material containing an inorganic compound or metal can include: a material formed from non-combustible paper or quasi-non-combustible paper having as a main component aluminum hydroxide, aluminum oxide, magnesium silicate, calcium silicate, or other inorganic component; material obtained by firing aluminum hydroxide, aluminum oxide, magnesium silicate, calcium silicate, or other inorganic component; and material formed from aluminum, stainless steel, copper, or the like.

If the substrate is a film, sheet, or nonwoven material, the thickness of the substrate 5 is preferably 1 μπι or more, 5 μπι or more, or 10 μπι or more and 1000 μπι or less, 500 μπι or less, or 100 μπι or less for example. For the honeycomb structure, the thickness is preferably within a range of 5 mm or more or 20 mm or more and 500 mm or less, 100 mm or less, or 50 mm or less for example.

The pressure-sensitive adhesive article 1 1 is used by pasting a main surface on an opposite side from the substrate 5 of the pressure-sensitive adhesive layer 2 to a concrete structure. The substrate 5 may be pre-pasted to the pressure-sensitive adhesive layer 2 before constructing, or a first pressure- sensitive adhesive layer 2 is pasted to a concrete structure and then the substrate 5 is pasted to a second pressure-sensitive adhesive layer 2. The thickness (shortest distance) Tl between a main surface on an opposite side from the substrate 5 of the pressure-sensitive adhesive layer 2 and a main surface of the fibrous sheet 3 is preferably 100 um or less, 80 μπι or less, or 50 μπι and 10 μπι or more, 20 μπι or more, or 30 μπι or more from the perspective of being able to suitably reinforce a concrete structure.

The thickness (shortest distance) between a main surface on the substrate 5 side of the pressure- sensitive adhesive layer 2 and a main surface of the fibrous sheet 3 is preferably 10 um or more or 20 μτη or more and 300 μπι or less or 100 μπι or less.

Before the pressure-sensitive adhesive article is applied on the concrete structure, a surface treating agent such as an acrylic adhesive, epoxy adhesive, or the like can be applied to a surface of the concrete structure, from the perspective of preventing cracking of a concrete structure. The surface treating agent may be an accelerated curing resin that curing accelerates when heat, light, moisture, or the like is applied. Furthermore, the applied surface treated layer may have a function as a primer layer with regard to the pressure-sensitive adhesive article.

The pressure-sensitive adhesive article 11 can be manufactured by the following method for example.

(1) A first pressure-sensitive adhesive layer is formed by applying a pressure-sensitive adhesive for example on the substrate 5, and the first pressure-sensitive adhesive layer is cured by irradiating ultraviolet light for example (may also be heat cured).

(2) The fibrous sheet 3 is provided on the first pressure-sensitive adhesive layer.

(3) A second pressure-sensitive adhesive layer is formed by applying a pressure-sensitive adhesive for example on the fibrous sheet 3, and the second pressure-sensitive adhesive layer is cured by irradiating ultraviolet light for example (may also be heat cured). Thereby, the pressure-sensitive adhesive article 11 is obtained.

The pressure-sensitive adhesive article 1 (FIG. 1) not providing the substrate 5 is obtained by removing the substrate 5 from the pressure-sensitive adhesive article 11 obtained as described above, for example.

The pressure-sensitive adhesive articles 1 and 11 can be constructed on a concrete structure 4 by the following method for example.

( 1) The surface treating agent is arbitrarily coated and dried on the concrete structure 4, and then if necessary, heat, light, or the like is applied to form the surface treated layer.

(2) The pressure-sensitive adhesive layer 2 of the pressure -sensitive adhesive articles 1 and 1 1 applied directly or through a surface treated layer onto the concrete structure 4.

(3) The substrate 5 is arbitrarily further applied onto the pressure -sensitive adhesive layer 2 on an opposite side of the concrete structure 4 of the pressure -sensitive adhesive article 1.

The pressure-sensitive adhesive article may be in a form other than the aforementioned embodiments. The pressure -sensitive adhesive article may provide a liner on one or both main surfaces of the pressure-sensitive adhesive layer for example. If the pressure-sensitive adhesive article provides a liner and substrate, the liner may be provided on the substrate.

The pressure-sensitive adhesive article of the present disclosure is suitable for preventing peeling off of a concrete piece from a concrete structure such as a bridge, tunnel, elevated road, or the like, and can suitably reinforce a concrete structure by simply directly applying the pressure-sensitive adhesive article on the concrete structure.

EXAMPLES

In the following examples, specific embodiments of the present disclosure are exemplified, but the present invention is not restricted thereto. All "parts" and "percents" are based on mass unless specified otherwise. Example 1

90 mass parts of 2-ethyl hexyl acrylate, 10 mass parts of acrylic acid, and 0.04 mass parts of a photopolymerization initiator (Irgacure 651, BASF Japan) were mixed. 0.5 mW/cm ² ultraviolet light was irradiated onto the obtained mixture, and irradiation was ended at the point in time when the viscosity of the mixture reached 1000 cps. 0.08 mass parts of 1,6-hexanediol diacrylate, 0.1 mass parts of a photopolymerization initiator (Irgacure 651), 1.5 mass parts of silica fine particles (A200, Nippon Aerosil Co., Ltd.), and 6 mass parts of glass hollow fine particles (K15, 3M Company) were added and stirred into the mixture after irradiating ultraviolet light and then cooled to 23°C to obtain a pressure-sensitive adhesive.

Next, an article was obtained where the pressure-sensitive adhesive layer containing the obtained pressure-sensitive adhesive and glass cloth (biaxial woven material, L 160MA100LF, Unitika Ltd.) provided on the pressure-sensitive adhesive layer were provided on a peelable liner (PET film: thickness of 38 μπι).

One more peelable liner was provided on a pressure-sensitive adhesive layer side of the article. Furthermore, 0.5 W/cm ² (total energy: 1 J) ultraviolet light was irradiated onto the article to obtain a pressure-sensitive adhesive article. The thickness of the pressure-sensitive adhesive layer of the obtained article was 1200 mm.

Example 2

An article was prepared similarly to example 1, except that the fibrous sheet was changed to a vinylon woven material.

Comparative example 1

A pressure-sensitive adhesive article was prepared similarly to example 1, except that silica fine particles and glass hollow fine particles were used.

Comparative example 2

An article was prepared similarly to example 1, except that the pressure-sensitive adhesive was changed to a butyl rubber pressure-sensitive adhesive.

Reference example 1

A pressure-sensitive adhesive article was prepared similarly to example 1, except that a glass cloth was used. Reference example 2

A pressure-sensitive adhesive article was prepared similarly to example 1, except that silica fine particles, glass hollow fine particles, and glass cloth were used.

The following concrete peeling prevention evaluation test was performed for the aforementioned pressure-sensitive adhesive articles.

Concrete Peeling Prevention Evaluation Test

Measurements were performed in accordance with NEXCO test method 424-201 1. First, as illustrated in FIG. 4 and 5, a core portion having a remaining portion with an inner diameter of 100 mm, groove width of 5 mm, and depth of 60 mm was formed by a core cutter for concrete, on a center of a concrete block 7 with a length of 400 mm, width of 600 mm, and height of 70 mm. The pressure-sensitive adhesive article 1 was applied on a surface opposite from the core portion of the concrete block 7. The construction area had a 400 mm length and 400 mm width. Next, as illustrated in FIG. 4 and 5, the concrete block 7 was installed at a position at height h or higher where the peeling preventing properties of the push- off testing machine 6 can be confirmed. The core portion of the concrete block 7 was loaded at a rate of 1 mm/min in the direction of the arrow through a spherical seat 8 until the remaining portion of the core portion was destroyed. After destroying, a forced displacement was applied on the pressure-sensitive adhesive article 1 by loading at a rate of 5 mm/min, and then the load and displacement were continuously recorded by a load meter 9 and displacement meter 10. Meanwhile, loading is temporarily suspended at displacements of 10 mm, 20 mm, and 30 mm, and then measurement (marking) of the peeling range of the pressure-sensitive adhesive article 1 was performed. If a final load bearing capacity was confirmed up until the displacement was 30 mm, the test was ended at this point in time. Furthermore, if a load bearing capacity was determined to be provided, loading was continued until approximately 50 mm. The results are shown in Table 1. Note that an article with a high maximum load and low maximum displacement amount exhibits excellent peeling preventing properties.

Table 1

[Description of Reference Numerals]

1 Pressure-sensitive adhesive article Adhesive layer

Fibrous sheet

Fibers

Concrete structure

Substrate

Push-off testing machine

Concrete block

Spherical seat

Load meter

Displacement meter